Combined carpet and spacer fabric



Jan. 2, 1962 B. H. FOSTER ETAL COMBINED CARPET AND SPACER FABRIC Filed April 23, 1958 2 SheetsSheet 1 WARP INVENTORS 5007/4 51 A l9. FflJ'TE/f WZM ATTORNEY Jan. 2, 1962 B. H. FOSTER ETAL 3,015,149

COMBINED CARPET AND SPACER FABRIC Filed April 23, 1958 2 Sheets-Sheet 2 INVENTORS 6007/7621 b. F0075? A AJJ/d #400,417

ATTORNEY 3,0l5,14 COMBINED CARPET AND SPACER FABRIC Boutwell H. Foster, Maplewood, and Nassib Haddad, Iselin, N.J., assignors to United States Rubber Company, New York, N.Y., a corporation of New Jersey Filed Apr. 23, 1958, Ser. No. 730,357 10 Claims. (Cl. 28--78) This invention relates to composite multi-ply fabrics suited for use as carpeting, upholstery covers and the like, and to a process of making such fabrics.

-It has heretofore been proposed to make a composite carpet or upholstery cover by adhering a pile fabric woven or produced in any desired manner to a sheet of sponge-like material, e.g. rug underlay. Such a product, however, suffers from a number of substantial disadvantages. Primarily, it is very costly to manufacture since, by its very nature, it requires a weaving or other pile fabric-forming operation, a sponge-forming operation, a sponge-applying operation and a sponge-setting operation, all of which must be carried out individually and consume considerable amounts of time. Furthermore, it is very difiicult to launder such a product properly in view of the fact that the sponge backing generally has, due to its porosity, a relatively great water-retaining capacity. Thus, extended drying periods subseqeut to a Washing may be required, which could conceivably lead to damaging of the sponge, and yet complete drying of the latter would not be assured. Still further, in such a combination sponge-pile type of product, the possibility of separation of the pile fabric from the sponge backing is always present and becomes greater the more the product is used.

The principal object of the present invention is, therefore, to provide a novel and improved multi-layer carpet or upholstery fabric which is soft and resilient without requiring the use of foam or sponge rubber backing means.

Another important object of the present invention is the provision of a multi-ply, pile-topped fabric made in its entirety of filaments, strands, yarns and the like woven in a single operation on a single loom so as to form and simultaneously interweave the various plies of the fabric.

It is still another object of the present invention to provide a fabric of the aforesaid type which is easy and inexpensive to manufacture and is free of the adhesion problems heretofore encountered in known sponge-backed pile fabrics.

It is also an object of the present invention to provide a pile-topped carpet and upholstery fabric which is more washable and considerably easier to dry than comparable known products.

A further object of the present invention is, therefore, the provision of a process of making a fabric as set forth above, which process is characterized especially by weaving and joining of all of the fabric plies on a single loom in one operation.

Still a further object of the invention is the provision of a process of making such a fabric which entails interweaving strands of highly contractile material with stiff strands of relatively non-contractile material and with soft strands of a different relatively non-contractile material in such a manner that a subsequent heat treatment te tates Patent causes shrinking of the contractile stands, corrugation of the stiff stands, and concurrent formation of the pile surface by buckling or bulging of the soft strands upwardly from the uppermost ply.

A related object of the invention is the provision of a fabric as aforesaid in which the pile-surface may be formed of strands all extending in the same direction as the highly contractile strands, i.e., warpwise or weftwise of the fabric as a Whole, or of interwoven strands some of which extend codirectionally with the contractile strands and the remainder of which extend transversely to these contractile strands.

More specifically, the method and the fabric produced thereby, according to one embodiment of the present invention, entail the interweaving on a single loom of substantially parallel, relatively highly heat-shrinkable warp strands and transverse picks of a preferably though not necessarily relatively non-heat-shrinkable material so as to form two outer layers or plies, while concurrently therewith, i.e., in the same operation and on the same loom, substantially stiff, relatively non-heat-shrinkable strands extending warpwise of said outer plies are interwoven alternately with spaced and staggered picks of the latter and therebetween so as to interconnect the plies, and soft, more or less limp and bulky, relatively nonheat-shrinkable strands of any suitable pile yarn extending warpwise of the outer plies are interwoven only with the upper one of said plies by being floated periodically over a plurality of the picks thereof. The ultimately woven flat multi-ply fabric is then removed from the loom and subjected to a controlled heat. treatment for the purpose of causing the shrinkable warp strands in the fabric to contract or shrink by a predetermined amount, as a result of which the entire fabric shrinks w-arpwise an amount ranging from about 25% to about 60% of its olf-the-loom length, thereby causing the stiff intermediate strands to buckle and form a corrugated intermediate layer or ply, while the soft strands are buckled upwardly and transformed into a pile-constitut ing series of bulges or buckles upstanding from the surface of the upper ply with which these soft strands were interwoven.

According to another embodiment of the invention, there are interwoven with the soft and non-shrinkable pile-forming warp strands themselves additional soft and non-shrinkable transverse picks of the same or different material as the said warp strands, whereby the pile top of the finished fabric is in essence an individual fabric in which are formed a series of parallel weftwise bulges or ridges substantially inverted trough-like in cross-section.

The design or pattern of the pile surface, as well as its density, fiufliness, porosity, and other physical characteristics are, of course, determined not only by the nature of the material of which the pile strands are formed, but also by the heat-shrinking properties of the warp strands of the aforesaid outer plies and by the eX- tent to which such warp strands are permitted to shrink during the heat treatment. With respect to the present invention, the terms heat-shrinkable and non-heatshrinkable, or their equivalents contractile and noncontractile, are not necessarily to be interpreted only in their absolute senses, since their connotations are quite definite even when considered with reference to any par ticular temperature range within which the Warp strands of the outer plies tend to shrink. As will be readily understood, the temperature at which the heat treatment is carried out must fall within this range which should be well below the softening or flow point of the shrinkable strands and, thus, even further below the temperatures at which the intermediate stiff strands, the picks or weft strands of the outer plies, and the pile strands tend to shrink or be otherwise adversely affected.

The foregoing and other objects and advantages of the present invention will become more fully clear from the following detailed description when read in conjunction with the accompanying drawing, in which:

FIG. 1 is a schematic, isometric view of a multi-ply, woven, pile-type carpeting or upholstery fabric according to the present invention;

FIG. 2 is a diagrammatic side elevational view of the fabric as seen in the weft direction in FIG. 1;

FIG. 3 is a drawing-in draft for a different type of multi-ply, pile-topped fabric according to the present invention;

FIG. 4 is a graphic representation of the weave chain for this fabric; and

FIG. 5 is a schematic, isometric view of yet another form of multi-ply fabric according to the present invention.

Referring now more particularly to FIGS. 1 and 2 of the drawing, it will be seen that according to one embodiment of the invention the fabric comprises a pilecovered top layer or ply 11, a bottom layer or ply 12, and an intermediate layer or ply 13, all interwoven with one another in a manner to be more fully described hereinafter. The top layer 11 is composed of highly contractile or heat-shrinkable warp strands 14 and relatively non-contractile weft strands 15. The bottom layer 12 is substantially identical with the top layer with respect to the characteristics of the weave, being composed of highly contractile warp strands 16 and relatively noncontractile weft strands 17. The intermediate layer 13 is composed of corrugated, stiff, relatively non-contractile warp strands 18.

For the purpose of implementing the principles of the present invention, the highly contractile warp strands 14 and 16' may be made of any suitable, thermoplastic, heat-shrinkable, synthetic material which should have the property, when in filamentary form, of shrinking under appropriate conditions by at least 25% and preferably by at least 40% upon being subjected to heat at a temperature below the softening or flow point of this material. Among the synthetic fibers which are suited for use in forming the shrinkable warp strands are polyethylene (an oriented polymerized ethylene), saran (a copolymer of vinyl chloride and vinylidene chloride) and in particular the so-called high-shrink saran, Verel (an acrylic fiber), Dynel (a copolymer of vinyl chloride and aorilonitrile), Rhovyline (a yarn spun from a blend of 70% nylon, i.e., a polyamide, and 30% Fibravyl staple), polypropylene, Rhovyl or Fibravyl (polyvinyl chloride), and Vinyon CFHST or Vinyon HH (a copolymer of vinyl chloride and vinyl acetate). It is to be understood, of course, that this list is illustrative only, and that other materials which are known to have similar heat shrinkage properties may be employed.

The picks or weft strands and 17 and the intermediate strands 18 preferably are made of synthetic materials which are relatively non-shrinkable under the heat treatment conditions to which the woven fabric is to be subjected. Suitable materials for this purpose are the so-called regular or low-shrink saran and Dacron (an oriented polyester of terephthalic acid with ethylene glycol), but other materials having similar physical properties may, of course, e employed if desired. Mere 1y by way of example, threads such as .010 saran and .012" saran have been found highly advantageous for use as picks or filling strands 15 and 17, while threads such as .0 12" saran or .020 saran have been found to be well suited for use as the stiif corrugatable strands 18.

The pile portion of the top layer 11 is formed of soft, preferably limp and bulky, Warpwise strands 19 interwoven with the top layer 11 in a manner to be more fully described hereinafter. These pile strands may be made of any suitable pile yarn, such as 6/2 viscose pile, 260 den. nylon and like materials having the common property of not being subject to any appreciable shrinkage upon application of heat at the chosen temperature of the treatment.

The temperature range within which the warp strand shrinkage takes place varies with the particular type of thermoplastic material employed and is a well known characteristic of each type of material. Moreover, it is known that as the upper end of the shrinkage temperature range for any particular material of this type is approached, the amount of further shrinkage taking place gradually decreases and finally becomes substantially negligible. Considering both polyethylene and Vinyon, for example, a major part of the shrinkage occurs in the range from about F. to F., but as the temperature rises further, the additional shrinkage becomes less and less until virtually no further change in length occurs above about 2.l0-212 F. Below about 150 F., the rates of change of shrinkage of these two materials differ to a greater extent, but this has no practical effect on the present invention. According to the invention, a

heat treatment in boiling water, i.e., at a temperature of about 200-212 F., has been found to be extremely advantageous and efficacious.

The method of producing the finished pile-topped fabric according to FIGS. 1 and 2, is, of course, greatly simplified by virtue of the fact that the entire fabric 10 is woven at one time on a loom by employing conventional weaving techniques. The strands 18, which are ultimately to constitute the intermediate layer 13, are interwoven alternately with selected spaced and staggered picks 15 and 17 of the top and bottom layers 11 and 12. As may be seen from FIG. 1, the first strand 18 (i.e., the one shown at the front of the figure) is interwoven alternately with a pick 15, then a pick 17, then a pick 15, then a pick 17, and so forth, each of these picks 15 being located intermediate two of the said picks 17, and vice versa. Similarly, the second strand 18 (i.e., the one shown immediately behind the aforesaid first strand) is interwoven with a pick 17, then a pick 15, then a pick 17, then a pick 15, and so forth, these last-named picks 17 and 15 being juxtaposed with respect to one another in the same manner as the first-mentioned picks 15 and 17. The next strand 18 is interwoven with the plies 11 and 12 in substantially the same way as the first strand, while the fourth strand is interwoven with the plies 12 and 11 in the same manner as the second strand, etc. Thus, the lines of connection between about one half of the strands 18 and the layers 11 and 12, as indicated by dash-dot lines 11a and 12a, respectively, are arranged in alternating sequence with the lines of connection between the remaining strands 18 and the bottom and top layers 12 and 11, as indicated by dash-dash lines 12b and 11b, respectively. In this manner, the strands 18 of the intermediate layer 13 actually serve as the means for securing the top and bottom layers to one another and ultimately, i.e., after the shrinkage treatment, for holding the top and bottom layers resiliently spaced apart.

The soft pile strands 19 are interwoven only with the top layer 11 by being floated, individually or in groups depending on the pile characteristics sought to be attained, over spaced picks 15 or spaced groups of such picks. In this embodiment of the fabric, the strands 19 are shown (for the sake of simplicity) as floated in groups of four over a number of picks 15, say five, and under a smaller number of picks 15, say one or two, intermediate any two adjacent groups of five picks. Generally, the upper surfaces of the groups of pile yarn warp strands 19 are substantially in one and the same plane, and the showing of a difference in elevation between such groups, as indicated in FIG. 2, is actually employed only to simplify the view of the fabric in side elevation. Nevertheless, it is to be noted that different pile yarn strand groups may be arranged at different elevations relative to the outer surface of the upper ply or layer 11. It will, of course, be readily appreciated that different weaving relationships may be employed. Thus, the pile strands 19 may be floated individually and in staggered arrangement alternately over and under single adjacent picks 15. Alternatively, the pile strands may be floated in groups of two or more and in staggered relation over six picks, under one or two, over one or two, under one or two, over six, and so forth. None of these patterns is, of course, intended as a limitation of the scope of the present invention, since the sole determining factors, as far as the details of the weaving operation are concerned, are the pile de sign, density, size and other physical characteristics to be attained.

After the fabric 1% has been woven and removed in flat form from the loom, it is subjected to an accurately controlled heat treatment. Advantageously, for the purpose of this invention, the flat fabric is run through or immersed in a hot water bath maintained at a temperature between about 150 F. and 212 F. and preferably through boiling water at about 210212 F. The duration of the immersion will, of course, depend on the type of heatshrinkable Warp strands employed in the top and bottom layers 11 and 12, and must be so predetermined as to ensure (if desired in conjunction with suitable auxiliary conditions, such as controlled external tension applied to the fabric as it passes through the hot water bath) that the warp strands 14 and 16 shrink sufficiently to cause the entire fabric to shrink warpwise by an amount ranging from about 25% to about 60% of its ofiE-the-loom length.

As a direct consequence of the shrinking of the warp strands 14 and 16 of the top and bottom layers 11 and 12, the relatively non contractile strands 18 are buckled or substantially sinusoidally corrugated to form a resilient intermediate layer having a considerable compression strength. Inasmuch as the top and bottom layers 11 and 12, therefore, are resiliently retained in spaced relationship by the intermediate layer 13, the fabric forms an essentially resilient cushion, as disclosed in U.S. Patent Re. 24,007, and air can pass freely through the fabric. This ventilation feature becomes of considerable importance where the fabric according to the present invention is used as a furniture or upholstery covering, insuring additional comfort for any person sitting on such furniture due to the relatively free access of air to the part of said person in contact with the upholstery covering.

Concurrently, and as a further direct consequence of the shrinking of the warp strands 14 and 16, the distances between the picks 15 of the top layer are decreased, and the portions of the pile strands 19 floated over the various picks are thus caused to buckle or bulge upwardly and stand out from the upper surface of the top layer 11 to constitute the pile top of the fabric. As illustrated in FIG. 1, the pile-constituting bulges in each warpwise row are staggered with respect to the bulges in the next adjacent warpwise row, thereby providing both raised and depressed pile surface regions extending substantially diagonally across the warpwise dimension of the fabric in the manner of a twill. Quite understandably, an almost infinite variety of pile surface patterns or designs may be attained by suitably varying the weaving operation with respect to the floating of the pile strands 19 over the picks or filling strands 15.

A multi-ply fabric according to another embodiment of the present invention is diagrammatically indicated in FIGS. 3 and 4. As previously stated, FIG. 3 represents the drawing-in draft for a fabric Woven with fourteen harnesses identified, respectively, by the numerals 1 to 14 at the left-hand side of the figure. Each heavy horizontal line at the base of the figure designates a dent of the reed. It will, of course, be understood that the draft sets forth only one repeat of the pattern. In FIG. 3, the xs represent heat-shrinkable polyethylene warp strands for the outer layers of the fabric, the 0s relatively non-contractile or non-heat-shrinkable strands of saran for the intermediate layer, and the as the pile yarn, e.g. viscose pile, with two pile yarn ends disposed in each heddle.

The weave chain for this fabric is shown in FIG. 4, in which the dots represent lowered warps while the crosses represent raised warps.

The fabric woven from the draft and weave chain of FIGS. 3 and 4, after being subjected to the required heat treatment as set forth hereinabove, is found to possess a dense pile surface substantially devoid of the gaps or spaces which characterize the fabric 10 of FIG. 1.

A multi-ply fabric according to still another embodiment of the present invention is illustrated schematically in FIG. 5. The fabric 11):: here shown basically comprises a top layer 11 composed of shrinkable Warp strands 14 and non-shrinkable weft strands or picks 15, a bottom layer 12 composed of shrinkable warp strands 16 and non-shrinkable weft strands or picks 17, and an intermediate layer 13 composed of relatively stiff, non-shrinkable and corrugated warpwise strands 1%. To the extent so far described, the fabric 10a is substantially identical with the fabric 111 of FIG. 1, and thus the same reference numerals have been employed to designate corresponding elements.

In lieu of a pile surface formed by individual pile yarn strands 19 extending warpwise of the fabric 11 however, the fabric 119a is provided with a raised surface formed by non-shrinkable Warp strands 21 which are themselves interwoven with non-shrinkable weft strands or picks 21. The warp strands 2i and the orthogonal strands 21 essentially make up a puffed fabric which is interlaced with the top layer 11, but it must be remembered that this puffed fabric is not formed individually, i.e., as a separate entity adapted to be adhered in any desired manner to the layer 11. Quite to the contrary, the puffed fabric is formed simultaneously with and by the same weaving operation as the layers 11, 12 and 13.

As illustrated in FIG. 5, the fabric 2021 is interwoven with the top layer 11 along a plurality of parallel weftwise lines coinciding substantially with the lines 11a and 11b designating the lines of connection between the said top layer and the corrugated strands 18. This is not a necessary condition, of course, since the puffed fabric may be interwoven with any desired ones of the picks 15 and not necessarily along parallel or even straight lines. When the fabric 141a is removed from the loorn and subjected to the prescribed heat treatment, the shrinkage causesupward bulging of the fabric 2-il-21 so as to form a plurality of parallel ridges of substantially inverted trough-like cross-section. This type of fabric is particularly well suited for use as a seat cushion or back rest upholstery covering due to its even more pronounced ventilating property. By way of refinement, the ridges of the pile fabric can be easily divided into shorter blocks, as by lioating some of the shrinkable warp strands 14 over predetermined groups of the non-shrinkable picks 21, whereby the surface will have a brick wall-type of appearance.

The invention will be more specifically illustrated by the following examples. Four fabrics, hereinafter identified by the numerals I, II, III and IV, respectively, were woven of a variety of shrinkable and non-shrinkable yarns on a loom in the manner disclosed hereinabove. Fabric I is essentially that illustrated in FIGS. 1 and 2, Fabric H is essentially that illustrated in FIGS. 3 and 4, and Fabric III is essentially that illustrated in FIG. 5. Upon being removed from the loom, the fabrics were tested to determine a number of off-the-loom characteristics and physical properties, whereafter these fabrics were passed individually through a hot water bath maintained at a temperature of 212 F. The rate of feed of the fabric into the hot water bath in each case was 6 yards per minute to ensure that all portions of each fabric were sub ected to the requisite heat treatment for a period of F b ZZZ-C ti d 0.5 m nute, the exit rate for each fabric being so selected,

i.e., set at 3.6 yards per minute, as to permit a shrinkage of 40%. The fabrics were now tested again to determine ohmmelsuc gag Shunk the effect of the shrinkage treatment on the above-men- L Percent Filling Cr mp:

tioned characterist cs. The results of the entire procedure Viscose 0 together with the compositions of the fabrics are set forth p0ly0tI1ylenot0p 1.

- polyethylenebottorn 1.0

111 2 following t Thickness at .1 psi. (in inches).

Percent Oompressibility at 2 p.s.i F abrlc I Percent Resilience Percent of Fabric:

nylon 17. 8

L .012 polyethylene-bottom. M... 7. 0

" viscose 25.8

Width (in inches) 11. 2 9 77 DLP polyethylene 4. 9

Weight (in OZ./Sq. yd.). 21. 03 38.7 DLP pq y y 8 Endslin.: Percent Shrinkage:

.012 polyethylene-top 22 25.5 Wid h 5. 28 .012 polycthyleneebottom 22 25. 5 61 21 .38. 7 .020 Sarancenter 22 25. 5 0/2 viscose pile-top 22 25. 5

Pi k /i 1 Linear polyethylene.

' .010 Saran-top 21 20. 75

.010" saianbottom 21 29.75 Fabrzc IV Percent Warp Crimp:

polyethylene.

Saran Characteristic Off the Shrunk viscose pile L om Percent Filling Crimp.

Thickness at .1 p.s.i. (in inclies) Percent Ccrripressibility at 2 p.s.1 Width (in inches) 29. 375 26. 44

Percent Resilience. Weight (in oz./sq. yd. 23. 2 41. 1

Percent of Fabric: Ends/111.:

polyethylene 18. 7 6/2 Rio visccsetop 25. 9 28.7 .020 Saran- 39.1 .012 polyethylenetop.. 25. 9 28. 7 V scose pile. 24. 6 .012 polyetliylene-bottoin 25. 9 28. 7 010 Sa 17.6 .012 saran-center 25. 0 28. 7

Percent Shrinkage: Picks/in;

' h 18. 2 36 8/2 viscose type 120Ftop 12.9 20. 9 29. 4 8/2 viscose type l21litop 12. 9 20. 0 .010 sarcn-top 12. 9 20. 9 P .010v%aran6b0tt0ni 12. 9 20. 9 ercen' ar IlLLl Z Fab, 11 6/2 Rio v scosel 7. 5

.012 polyethylenetop 21.0

.012 polyethylene-bottom. 2.0

Characteristic On the Shrunk .012 saran 2.0

Looni Percent Filling Crimp:

8/2 viscose type 120F 7. 4

" 8/2 viscose type 12111 7. 4

Width (in inches) 9. 05 9.19 .010 sara'n-top 5.0

Weight (in oz./sq. yd.) 24. 0 41. 6 .010 saran-hottorn 5. 0

Ends/in: Thickness at .1 p.s.i. (in inches) 6/2 viscose pile-top 41. 0 44. 4 49 Percent Compressibility at 2 p.s.i

.012 polyethylene-top... 30. 75 33. 3 Percent Resilience .012 polyethylene-bottom- 10.25 11. 1 Percent of Fabric:

.020 saran-center 20. 5 22. 2 6/2 Rio viscose 28. 2

Picks/1r; .012 polyethylene 11.2

.012 sai-antop 10. 5 17. 5 .012 p0lyethylenebctt 10. 5 .012 saranbottom 10.5 17. 5 .012 Saran 16. 1

Percent Warp Crimp: 8/2 viscose type 1202 11.9

' viscose pile 5. 2 8/2 viscose type 121E l0. 7 polyethylene-top-.. 5. 2 .010 sarantop 5. 7 polyethylene-bottom 3. 8 .010" siranbottoin 5. 7 saran 1.8 Percent Shrinkage:

Percent Filling 0 1.6 idt 9. 86

Thickness at .1 p.s.l. (i v 38. 2

Percent Compressibility at 2 p.s

Percent Resilience i 1 Pe p aP 41 1 It is, of course, understood that the present invention is f{i.i.i;g:g0 usceptible to a number of changes as regards the struclB 8;, 3-3 ture of the fabric and the method of making such a fabric, n

. n ne of which changes involve any departure from the Satan-bottom 5; Sc pe of the invention as disclosed hereinabove and as Percent Shrinkage:

width... 7. 7s fined in the appended claims. Merely by way of exlenglh 4 ample, it will be realized that the number of intermediate strands 18 per unit of weftwise dimension of the outer F b i 111 plies 11 and 12 can be varied at will to meet any desired or preset resiliency, compressibility of stiffness characteristics of the fabric. The only invariable factor encoun- Chara teristic Ofi the Shrunk c Loom tered is that the intermediate strands 18 as well as the pile strands 19 or 20 to be bulged upwardly must extend Width (in inches): in the same direction as the heat-shrinkable strands 14 tot y.-. 3E g and 16. Thus, the heat-shrinkable strands 14 and 16, g ei iitniibt stifytiffi. 14195 260 d c ns quent y the strands 18 and 12 also, may be I]. S 111..

260 den. ny1on wp 6m 7M Woven wcftwise rather than as warps. If shrinkage in .0121 polyetliylenetop. 29.25 32.25 plies 11 and 12 is desired transverse to shrinkable strands I 1 6%,, g gfi ggt j ff ff f g 4 and 16, strands 15 and 17 may also be shrinkable. Picks/in: The rriulti-ply fabrics produced solely by Weaving and igg ffififlii fifi iggg g g gg iggg ""1; otherwise treating a Variety of shrinkable ar d non-shrink- 0 /0 501A p0 y thy1ene-bottom 13. 74 22.4 able strands of synthetic or natural fibers in accordance Percent Warp Crimp: 14 2 with the principles of the present invention are found to nylon I p y y e p 4. o be highly serviceable and capable of being easily laundered polyethylene-both) 4.0 d

Saran 1.0 11 er all ordinary conditions. The various fabric lies,

Q by virtue of being permanently interconnected through interweaving of the diiferent strands, are immune to separation from one another desipite frequent laundering of the fabric and regardless of the extent of use thereof. Moreover, the resistance of such fabrics to a real deformation during use, i.e., their dimensional stability under adverse conditions, is considerably greater than that of comparable known fabrics. It will be appreciated that such physical characteristics are highly desirable for fabrics intended to be employed as carpeting, automobile seat covers, furniture and upholstery covers, and the like.

Having thus described our invention, what we claim and desire to protect by Letters Patent is:

1. A fabric for use as upholstery covering, carpeting, and the like, comprising upper and lower plies each composed of longitudinally shrunk strands extending in one direction of said plies and interwoven with strands extending substantially transverse to both said direction and said shrunk strands, an intermediate ply of unshrunk, stiff, corrugated strands extending substantially in said direction and inerwoven alternately with spaced ones of said transverse strands of said upper and lower plies, respeo tively, and a plurality of unshrunk pile yarn strands interwoven with said transverse strands of said upper ply so as to form in each of said soft strands raised pile-constituting buckles spaced from one another along said direction said upper ply forming the only fabric interconnection between said intermediate ply and said pile yarn strands.

2. A fabric for use as upholstery covering, carpeting, and the like, comprising a plurality of codirectionally extending, longitudinally shrunk strands of synthetic fibers interwoven with a plurality of strands extending transversely to said shrunk strands so as to form two individual plies, a plurality of unshrunk, relatively stiff and corrugated strands of synthetic fibers disposed between said plies and extending codirecu'onally with said shrunk strands and alternatingly interwoven with spaced ones of said transverse strands of said plies so as to connect said plies to one another and to space the same resiliently from one another, and a plurality of unshrunk yarns at least some of which extend codirectionally with said shrunk strands and said corrugated strands and are interwoven with said transverse strands of one of said plies at the surface thereof remote from the other of said plies, said unshrunk yarns being buckled outwardly of said one ply to constitute a raised surface for the fabric said one ply forming the only fabric interconnection between said corrugated strands and said unshrunk yarns.

3. A fabric according to claim 2, others of said unshrunk yarns extending transversely to said shrunk strands and said corrugated strands and interwoven with the firstnamed unshrunk yarns.

4. A fabric for use as upholstery covering, carpeting, and the like, comprising upper and lower plies each composed of longitudinally shrunk warp strands interwoven with weft strands, an intermediate ply of unshrunk, stiff,

corrugated warp strands interwoven alternately with spaced and staggered ones of said weft strands of said upper and lower plies, respectively, and a plurality of unshrunk pile yarn warp strands interwoven with said Weft strands of said upper ply so as to form in each of said pile yarn strands a plurality of raised pile-constituting bulges spaced from one another warpwise of said plies said upper ply forming the only fabric interconnection between said corrugated warp strands and said unshrunk pile yarns.

5. A fabric according to claim 4, said warp strands of said upper and lower plies being shrunk after termination of the weaving operation to ensure shrinking of said fabric by an amount ranging from about 25% to about of its oif-the-loorn length.

6. A fabric according to claim 4, said weft strands being unshrunk.

7. A fabric according to claim 4, said stiff, corrugated strands of said intermediate ply being so arranged that the corrugations of each of said stiff strands are offset relative to the corrugations of the next adjacent stiff strands.

8. A fabric according to claim 4, further comprising a plurality of unshrunk pile yarn weft strands interwoven only with said pile yarn warp strands so as to define with the latter a puffed fabric the bulges of which are of inverted trough-like shape in cross-section.

9. A fabric for use as upholstery covering, carpeting, and the like, comprising upper and lower plies each composed of longitudinally shrunk warp strands of synthetic fibers interwoven with unshrunk picks of synthetic fibers, a plurality of unshrunk, relatively stiff and corrugated Warp strands of synthetic fibers disposed between and interlaced at the apices of their corrugations with respective spaced ones of said picks of said plies to thereby connect said plies to and resilently space the same from one another, a plurality of unshrunk pile yarn warp strands interwoven with said unshrunk picks of said upper ply and bulging upwardly from the latter, and a plurality of unshrunk pile yarn picks interwoven with said pile yarn warp strands said upper ply forming the only fabric interconnection between said corrugated warp strands and said unshrunk pile yarns.

10. A fabric according to claim 9, said pile yarn picks being further interwoven with said shrunk warp strands of said upper ply.

References Qited in the file of this patent UNITED STATES PATENTS 2,117,954 Greenwood May 17, 1938 2,231,388 Kahil Feb. 11, 1941 2,607,104 Foster Aug. 19, 1952 FOREIGN PATENTS 145,840 Australia Mar. 24, 1952 

1. A FABRIC FOR USE AS UPHOLSTERY COVERING, CARPETING AND THE LIKE, COMPRISING UPPER AND LOWER PLIES EACH COMPOSED OF LONGITUDINALLY SHRUNK STRANDS EXTENDING IN ONE DIRECTION OF SAID PLIES AND INTERWOVEN WITH STRANDS EXTENDING SUBSTANTIALLY TRANSVERSE TO BOTH SAID DIRECTION AND SAID SHRUNK STRANDS, AN INTERMEDIATE PLY OF UNSHRUNK, STIFF CORRUGATED STRANDS EXTENDING SUBSTANTIALLY IN SAID DIRECTION AND INTERWOVEN ALTERNATELY WITH SPACED ONES OF SAID TRANSVERSE STRANDS OF SAID UPPER AND LOWER PLIES, RESPECTIVELY, AND A PLURALITY OF UNSHRUNK PILE YARN STRANDS INTERWOVEN WITH SAID TRANSVERSE STRANDS OF SAID UPPER PLY SO AS TO FORM IN EACH SAID SOFT STRANDS RAISED PILE-CONSTITUTING BUCKLES SPACED FROM ONE ANOTHER ALONG SAID DIRECTION SAID UPPER PLY FORMING THE ONLY FABRIC INTERCONNECTION BETWEEN SAID INTERMEDIATE PLY AND SAID PILE YARN STRANDS. 